WO2016137965A1 - Élément d'espacement pour séparation membranaire - Google Patents

Élément d'espacement pour séparation membranaire Download PDF

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Publication number
WO2016137965A1
WO2016137965A1 PCT/US2016/019089 US2016019089W WO2016137965A1 WO 2016137965 A1 WO2016137965 A1 WO 2016137965A1 US 2016019089 W US2016019089 W US 2016019089W WO 2016137965 A1 WO2016137965 A1 WO 2016137965A1
Authority
WO
WIPO (PCT)
Prior art keywords
nodes
feed spacer
membrane separation
node
strands
Prior art date
Application number
PCT/US2016/019089
Other languages
English (en)
Inventor
Christopher James Zwettler
Alexander James Kidwell
Original Assignee
Conwed Plastics Llc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Conwed Plastics Llc filed Critical Conwed Plastics Llc
Priority to US15/553,079 priority Critical patent/US20180071688A1/en
Publication of WO2016137965A1 publication Critical patent/WO2016137965A1/fr

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D63/00—Apparatus in general for separation processes using semi-permeable membranes
    • B01D63/10—Spiral-wound membrane modules
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
    • B01D61/02—Reverse osmosis; Hyperfiltration ; Nanofiltration
    • B01D61/025—Reverse osmosis; Hyperfiltration
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2313/00—Details relating to membrane modules or apparatus
    • B01D2313/14—Specific spacers
    • B01D2313/143—Specific spacers on the feed side

Definitions

  • the present application relates to a feed spacer. More specifically, the present application relates to a feed spacer for spiral wound elements used for a pressure driven membrane separation process.
  • These pressure driven membrane separation processes include microfiltration, ultrafiltration, nanofiltration and reverse osmosis.
  • Membrane separation is commonly employed to extract pure or drinkable water from salt water and brackish water.
  • Spiral wound elements are used that employ osmotic filtration membranes. Frequently spiral wound elements can result in large pressure gradients across them.
  • the membranes are separated by a feed spacer net that can keep the membranes at a prescribed separation distance.
  • the feed spacer also allows tangential flow of the pressurized input water between adjacent filtration membranes.
  • a spacer net that produces a minimal drop in pressure as water flows through it and it resists accumulation of mineral and organic deposits can be desired.
  • the spacer can also impart minimum deformation into the membrane surface during use and during assembly of the element.
  • Embodiments disclosed herein include a spacer for membrane separation systems, the spacer comprising a plurality of nodes, wherein the nodes are tapered in the direction of flow through the membrane separation system; and a plurality of strands, wherein at least one strand connects each node to another node.
  • the plurality of nodes comprises perimeter nodes and internal nodes.
  • the internal nodes are connected to four nodes by four different strands.
  • each node comprises an upstream portion and a downstream portion.
  • a top portion of each node is substantially planar.
  • a bottom portion of each node is substantially planar.
  • a top portion and bottom portion of each node are substantially planar.
  • the surfaces on the top portion and bottom portion of each node are parallel.
  • two strands are connected to the downstream portion.
  • the two strands that are connected to the downstream portion form an arc that is concaved in the direction of the flow.
  • the plurality of nodes is arranged in rows and columns.
  • each of the internal nodes is directly connected by at least one strand to each of the four nearest nodes that are not in the same row or column.
  • the feed spacer is monolithic.
  • the upstream portion of each of the internal nodes is directly connected to the downstream portion of two nodes.
  • downstream portion of each of the internal nodes is directly connected to the upstream portion of two nodes.
  • the upstream portion of each of the internal nodes is directly connected to the downstream portion of two nodes; and the downstream portion of each of the internal nodes is directly connected to the upstream portion of two nodes.
  • the feed spacer defines a plurality of apertures.
  • an aperture is defined by at least four strands and at least two nodes.
  • a feed spacer for membrane separation system comprises: a plurality of nodes connected by a plurality of strands, wherein each node comprises a planar top surface and a planar bottom surface; and the top surface is parallel to the bottom surface.
  • a feed spacer for membrane separation system comprises: a plurality of nodes, wherein each node comprises an upstream portion and a downstream portion, and a plurality of strands, wherein at least two strands are connected to the downstream portion of each of the plurality of nodes, and the two strands connected to a downstream portion of a node are non-linear and define an arc that is concaved in the direction of the flow.
  • FIG. 1 is a top view of a feed spacer, according to an embodiment.
  • FIG. 2 is an enlarged top view of a portion of the spacer shown in FIG. 1, according to an embodiment.
  • FIG. 3 is a side view of a portion of a feed spacer, according to an
  • FIG. 4 is a top view of a node, according to an embodiment.
  • FIG. 5 is a side view of a node, according to an embodiment.
  • FIG. 6 is a chart showing the modeling of pressure drop across two different feed spacers, according to an embodiment.
  • FIG. 7 is a chart showing the modeling of pressure drop across two different feed spacers, according to an embodiment.
  • FIG. 8 is chart showing the modeling of velocities across two different feed spacers, according to an embodiment.
  • FIG. 9 is chart showing the modeling of velocities across two different feed spacers, according to an embodiment.
  • Membrane separation is a water purification technology that can be used to desalinate salt water or produce clean water from brackish water.
  • Membrane separation systems can have an input of salt water or brackish water and output of pure water or substantially pure water.
  • Membrane separation system can also have an output of salty water or other contaminants that were included in the input but removed from the pure water output.
  • a membrane separation system can include an input, an assembly, a first output and a second output.
  • the input can include salt water or brackish water.
  • the input can include a liquid that will be separated into a pure liquid and contaminants.
  • the assembly can separate the contaminants from the pure liquid.
  • the assembly can separate salt from water.
  • the assembly can include layers of a membrane separated by a feed spacer.
  • the membrane can be semipermeable.
  • the feed spacer can include a polymer such as a thermoplastic, a thermoset plastic, or an elastomer.
  • the polymer can include one or more of nylon, polyethylene, or polystyrene.
  • the feed spacer can be injection molded, such that in various embodiments, the feed spacer can include a polymer that is able to be injection molded.
  • the system can have two outputs, a first output and a second output.
  • the first output can include pure water or substantially pure water.
  • the first output can be substantially pure water, such that it is safe for human consumption or can be considered potable water.
  • the first output can be substantially free of contaminants, such as the contaminants that are a portion of the second output.
  • the second output can include contaminants, such as salt or bacteria.
  • the second output can be separated from the first output, such as within the assembly.
  • the assembly can include a feed spacer and a membrane.
  • the assembly can include a plurality of feed spacers and a plurality of membranes.
  • the assembly can include a feed spacer between two adjacent membranes, such that the assembly can include alternating membranes and feed spacers.
  • the flow can be generally tangential to the feed spacers and the membranes, such that the flow goes across the feed spacers and membranes and in some cases the flow can go through a feed spacer and/or a membrane.
  • the feed spacer 210 can include a plurality of nodes and a plurality of strands.
  • the nodes can be substantially similar, such as having the same shape and size.
  • each node can have a top surface, such as a flat or planar surface. The top surface can contact a membrane.
  • each node can have a bottom surface, such as a flat or planar surface. The bottom surface can contact a membrane.
  • the top surface and the bottom surface can be parallel.
  • the height of each node can be the distance from the top surface to the bottom surface. In various embodiments, the height of the nodes defines the distance between each membrane.
  • FIG. 1 shows a top view of a feed spacer 210, according to an embodiment.
  • the feed spacer 210 can be monolithic, such as when the feed spacer 210 is injection molded.
  • the feed spacer 210 can be monolithic, such that the feed spacer 210 is formed as a single piece of material, such as a single piece of polymer.
  • the feed spacer 210 can include a plurality of nodes 316 and a plurality of strands 318. At least one strand can be connected to each node. At least one strand can connect each node 316 to at least one other node 316. In some embodiments, the majority of the nodes 316 are connected to at least four strands 318. In various embodiments, each strand 318 can be connected to two nodes 316.
  • the flow across the feed spacer can be represented by arrow 320.
  • each node 316 can be tapered in the direction of flow across the feed spacer 210.
  • Each node 316 can be tapered, such that the upstream portion of the node is thicker or wider than a downstream portion of the node.
  • the downstream portion of node can be the thinnest or least wide portion of the node 316.
  • the downstream portion of the node 316 can come to a point.
  • the nodes 316 can be arranged into rows and columns within the feed spacer 210.
  • the rows can be staggered, such as every other row is aligned, such as the first row, the third row and the fifth row are all aligned together, and the second row, the fourth row and the sixth row are all aligned together (as shown in FIG. 1).
  • each row can be offset from the previous row or the following row by half of the distance between each node 316 in the row, such that nodes in second row are aligned with the halfway point between nodes in the first row and/or the third row.
  • the columns can be staggered, such as every other column is aligned, such as the first column, the third column and the fifth column are all aligned together, and the second column, the fourth column and the sixth column are all aligned together (as shown in FIG. 1).
  • each column can be offset from the previous column or the following column by half of the distance between each node 316 in the column, such that nodes in second column are aligned with the halfway point between nodes in the first column and/or the third column.
  • each row of nodes 316 can be separated by about 0.25 inches, such as the distance between nodes is about 0.25 inches. In an embodiment, each row of nodes 316 can be separated by about 0.25 inches, such as the distance between the centers of two nodes in adjacent rows is about 0.25 inches.
  • each row of nodes 316 can be separated by at least 0.125 inches and not more than 0.375 inches. In an embodiment, each row of nodes 316 can be separated by at least 0.2 inches and not more than 0.3 inches.
  • each column of nodes 316 can be separated by about 0.25 inches, such as the distance between nodes is about 0.25 inches. In an embodiment, each column of nodes 316 can be separated by about 0.25 inches, such as the distance between the centers of two nodes in adjacent columns is about 0.25 inches.
  • each column of nodes 316 can be separated by at least
  • each column of nodes 316 can be separated by at least 0.2 inches and not more than 0.3 inches.
  • Strands 318 can link together nodes 316. Strands can extend from one node 316 to another node 316. In some embodiments, the strands 318 can have a circular cross-section. In some embodiments, the strands 318 can have an oval cross-section. In some embodiments, the strands 318 can have a rectangular or square cross-section. In various embodiments, a strand 318 can link a downstream portion of a node 316 to an upstream portion of an adjacent node 316.
  • the strands 318 can have a thickness of about half of the thickness of a node
  • the strands 318 can have a thickness of at least 40% the thickness of a node 316 and not more than 60% the thickness of a node 316. In an embodiment, the strands 318 can have a thickness of at least 25% the thickness of a node 316 and not more than 75% the thickness of a node 316.
  • the plurality of nodes 316 can include perimeter nodes
  • Perimeter nodes 322 can refer to nodes 316 located around the perimeter of the feed spacer 210. In some embodiments, one or more of the perimeter nodes 322 can be coupled to a single strand 318 or two strands 318. The perimeter nodes 322 can be coupled to fewer strands 318 that link the node to an adjacent node, because, in various embodiments, the perimeter nodes 322 do not have nodes in each direction, since the perimeter nodes 322 is located around the perimeter of the nodes 316 of the feed spacer 210.
  • each internal node 324 can be directly connected to four strands 318. In various embodiments, each of the four strands connected to an internal node 324 can couple the internal node 324 to four adjacent nodes 316.
  • the four adjacent nodes 316 can include one or more perimeter nodes 322 and/or one or more internal nodes 324. In an embodiment, each internal node 324 is connected to four adjacent nodes 316 by four different strands 318. In an embodiment, each of the internal nodes 324 is directly connected by at least one strand 318 to each of the four nearest nodes 316 that are not in the same row or column.
  • FIG. 2 shows a top view of a portion of a feed spacer 210, according to an embodiment.
  • the direction of flow across the feed spacer 210 is represented by arrow 426.
  • Each node 316 can include an upstream portion 428 and a downstream portion 430.
  • the node 316 can taper from the upstream portion 428 to the downstream portion 430.
  • the node 316 can have a tear drop shape.
  • two strands 318 can be connected to the downstream portion 430 of each node 316. In various embodiments, two strands 318 can be connected to the upstream portion 428 of each node 316. In some embodiments, the two strands 316 that are connected to the downstream portion 430 can form an arc, such as an arc that is concaved in the direction of the flow. The arc can be concaved downstream, such as shown in FIG. 2.
  • the strands 318 can have one end connected to the upstream portion 428 of a node 316 and the opposite end connected to the downstream portion 430 of a different node 316.
  • every internal node 324 can have two strands 318 from its upstream portion 428, each strand 318 extending to a different downstream portion 430 of an adjacent node 318.
  • every internal node 324 can have two strands 318 from its downstream portion 430, each strand 318 extending to a different upstream portion 428 of an adjacent node 318.
  • the feed spacer 210 can define a plurality of apertures 432.
  • each aperture 432 can be defined by at least a portion of four strands 318 and at least a portion of two nodes 316.
  • each aperture 432 can be defined by at least a portion of four strands 318 and at least a portion of four nodes 316.
  • FIG. 3 shows a side view of a portion of a feed spacer 210, according to an embodiment.
  • the direction of flow across the feed spacer 210 is represented by arrow 534.
  • the node 316 can include a top surface 536 and a bottom surface 538.
  • the strands 318 can extend from an approximate midpoint between the top surface 536 and the bottom surface 538, such as shown in FIG. 3.
  • the top surface of the strands 318 can be aligned with the top surface 536.
  • the bottom portion of the strands 318 can be aligned with the bottom surface 538.
  • FIG. 4 shows a top view of a node 318, according to an embodiment.
  • the direction of flow past the node 316 is represented by arrow 640.
  • the node 316 can be tapered in the direction of flow.
  • the perimeter of the top of the node 316 can include non-linear segments.
  • the perimeter of the top of the node 316 can be tear drop shaped.
  • FIG. 5 shows a side view of a node 316, according to an embodiment.
  • the top surface 536 of the node 316 can be planar or flat.
  • the bottom surface 538 of the node 316 can be planar or flat.
  • the top surface 536 can be parallel with the bottom surface 538.
  • FIGS. 6 to 9 show the results of modeling.
  • the modeling shows the calculated pressure drops and velocities across different spacers.
  • a control spacer was used.
  • the control spacer was a commercial 34 mil blue spacer.
  • a spacer as described herein was used, referred to as a streamline spacer.
  • FIG. 6 shows a chart depicting the results of modeling pressure drop across the two feed spacers.
  • the streamline feed spacer has approximately a 33% less pressure drop over the feed spacer as compared to the commercial feed spacer.
  • FIG. 7 shows the pressure drop modeling across the two different feed spacers.
  • FIG. 7 shows the pressures at different locations across the feed spacers.
  • the commercial feed spacer had a 0.10 psi pressure drop.
  • the streamline feed spacer had a 0.058 psi pressure drop, a 42% smaller pressure drop compared to the commercial feed spacer. Further, it is evident from the model shown in FIG. 7, that the feed spacer has higher or equal pressure values than the commercial feed spacer at the majority of locations on the feed spacer.
  • FIG. 8 shows the velocity modeling across two different feed spacers.
  • the streamlined feed spacer has considerably more locations where the velocity is between 0.300 m/s and 0.450 m/s.
  • the commercial feed spacer has considerably more locations where the velocity is between 0.100 m/s and 0.300 m/s.
  • FIG. 9 shows a histogram of the velocities across the commercial feed spacer and the streamline feed spacer. Similar to FIG. 8, the streamlined feed spacer has considerably more locations where the velocity is between 0.300 m/s and 0.450 m/s and the commercial feed spacer has considerably more locations where the velocity is between 0.100 m/s and 0.300 m/s. The streamline feed spacer has more locations within the desired range of velocities compared to the commercial feed spacer.
  • the phrase “configured” describes a system, apparatus, or other structure that is constructed or configured to perform a particular task or adopt a particular configuration to.
  • the phrase “configured” can be used interchangeably with other similar phrases such as arranged and configured, constructed and arranged, constructed, manufactured and arranged, and the like.

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Water Supply & Treatment (AREA)
  • Nanotechnology (AREA)
  • Separation Using Semi-Permeable Membranes (AREA)

Abstract

Selon des modes de réalisation, l'invention concerne un élément d'espacement d'alimentation, pour un système de séparation membranaire, qui comporte : une pluralité de nœuds, les nœuds se rétrécissant dans la direction d'écoulement à travers le système de séparation membranaire, et une pluralité de brins, au moins un brin reliant chaque nœud à un autre nœud. Dans un mode de réalisation, un élément d'espacement pour un système de séparation membranaire comporte une pluralité de nœuds, chaque nœud comprenant une partie amont et une partie aval, et une pluralité de brins, au moins deux brins étant reliés à la partie aval de chaque nœud de la pluralité de nœuds, les deux brins reliés à la partie aval d'un nœud étant non linéaires et définissant un arc qui est concave dans la direction de l'écoulement. L'invention concerne également d'autres modes de réalisation.
PCT/US2016/019089 2015-02-23 2016-02-23 Élément d'espacement pour séparation membranaire WO2016137965A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US15/553,079 US20180071688A1 (en) 2015-02-23 2016-02-23 Spacer for membrane separation

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US201562119795P 2015-02-23 2015-02-23
US62/119,795 2015-02-23

Publications (1)

Publication Number Publication Date
WO2016137965A1 true WO2016137965A1 (fr) 2016-09-01

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WO (1) WO2016137965A1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108176235A (zh) * 2018-01-19 2018-06-19 南京工业大学 一种新构型隔网
WO2018221103A1 (fr) * 2017-05-30 2018-12-06 東レ株式会社 Élément de membrane de séparation

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3870435A1 (fr) 2018-10-23 2021-09-01 Politechnika Slaska Piece d'écartement avec éléments de mélange, en particulier pour modules membranaires

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Publication number Priority date Publication date Assignee Title
US20040226877A1 (en) * 2003-05-16 2004-11-18 Karode Sandeep K. Feed spacers for filtration membrane modules
US20080190836A1 (en) * 2005-10-31 2008-08-14 Masashi Beppu Spiral Separation Membrane Element
US20090014359A1 (en) * 2004-10-11 2009-01-15 Johannes Leendert Willem Den Boestert Process for separating colour bodies and/or asphalthenic contaminants from a hydrocarbon mixture
WO2013085755A2 (fr) * 2011-12-09 2013-06-13 General Electric Company Espaceurs d'alimentation pour élément membranaire enroulé en spirale
US20130341264A1 (en) * 2012-06-26 2013-12-26 Conwed Plastics Llc Membrane filtration using low energy feed spacer

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20040226877A1 (en) * 2003-05-16 2004-11-18 Karode Sandeep K. Feed spacers for filtration membrane modules
US20090014359A1 (en) * 2004-10-11 2009-01-15 Johannes Leendert Willem Den Boestert Process for separating colour bodies and/or asphalthenic contaminants from a hydrocarbon mixture
US20080190836A1 (en) * 2005-10-31 2008-08-14 Masashi Beppu Spiral Separation Membrane Element
WO2013085755A2 (fr) * 2011-12-09 2013-06-13 General Electric Company Espaceurs d'alimentation pour élément membranaire enroulé en spirale
US20130341264A1 (en) * 2012-06-26 2013-12-26 Conwed Plastics Llc Membrane filtration using low energy feed spacer

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2018221103A1 (fr) * 2017-05-30 2018-12-06 東レ株式会社 Élément de membrane de séparation
CN110691640A (zh) * 2017-05-30 2020-01-14 东丽株式会社 分离膜元件
KR20200011940A (ko) * 2017-05-30 2020-02-04 도레이 카부시키가이샤 분리막 엘리먼트
JPWO2018221103A1 (ja) * 2017-05-30 2020-03-26 東レ株式会社 分離膜エレメント
US11123691B2 (en) 2017-05-30 2021-09-21 Toray Industries, Inc. Separation membrane element
CN110691640B (zh) * 2017-05-30 2022-04-26 东丽株式会社 分离膜元件
KR102404191B1 (ko) * 2017-05-30 2022-05-30 도레이 카부시키가이샤 분리막 엘리먼트
CN114602327A (zh) * 2017-05-30 2022-06-10 东丽株式会社 分离膜元件
JP7478510B2 (ja) 2017-05-30 2024-05-07 東レ株式会社 分離膜エレメント
CN114602327B (zh) * 2017-05-30 2024-05-10 东丽株式会社 分离膜元件
CN108176235A (zh) * 2018-01-19 2018-06-19 南京工业大学 一种新构型隔网

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